TIN for Canadian company issuing NR4 form - TurboTax Support Group could not help with the required information. Searching the internet I was finally able to find that the information is actually an EIN with the corresponding number for each company search separately.
Paid Foreign taxes section - I would suggest an adjustment to the Foreign Income section to allow foreign taxes paid to be reported quarterly, rather than with the suggested end of the year date. This may help dodge a surprise penalty for "estimated taxes not paid" which TurboTax has built into the system on behalf of the IRS.